Where can I find the Trustpilot ID?

Get your ID.To obtain your Trustpilot ID, first login to the admin panel at http://b2b.trustpilot.com/Modules/Plugins.
Then navigate to Integrations -> Other Integrations -> JSON Feed and click on "I'm Interested". This wil open the JSON Feed configuration page (see left screenshot).

The Trustpilot ID is the number within the feed url, e.g. http://s.trustpilot.com/tpelements/917278/f.json.gz would give ID: 917278